I'm not sure I understand the scale here; there is often not a number of usage to addition, it's often a matter of sustained and/or heavy usage. Yes, some drugs

I'm not sure I understand the scale here; there is often not a number of usage to addition, it's often a matter of sustained and/or heavy usage. Yes, some drugs lower that threshold (and I thought cigarettes were much more addictive than alcohol), but it's not a x-time-and-done issue. Also, note the lack of caffeine on the chart, it being very common drug that is highly addictive